21768182077180 has 144 divisors (see below), whose sum is σ = 58016190024576. Its totient is φ = 6784256545920.

The previous prime is 21768182077171. The next prime is 21768182077181. The reversal of 21768182077180 is 8177028186712.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21768182077181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 123267307 + ... + 123443773.

It is an arithmetic number, because the mean of its divisors is an integer number (402890208504).

Almost surely, 2^{21768182077180} is an apocalyptic number.

21768182077180 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21768182077180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29008095012288).

21768182077180 is an abundant number, since it is smaller than the sum of its proper divisors (36248007947396).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21768182077180 is a wasteful number, since it uses less digits than its factorization.

21768182077180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187944 (or 187935 counting only the distinct ones).

The product of its (nonzero) digits is 4214784, while the sum is 58.

The spelling of 21768182077180 in words is "twenty-one trillion, seven hundred sixty-eight billion, one hundred eighty-two million, seventy-seven thousand, one hundred eighty".